TELUS emailed us to say their Extend service still remains in beta as they “continue to test the platform for an optimal experience” before its pubic release:

TELUS Extend lets TELUS customers use their TELUS number on their smartphone, tablet or laptop to send and receive calls or messages anywhere in North America over Wi-Fi networks. TELUS Extend is currently an invitation-only Beta version – for iOS, Android, PC’s and Mac OS X – as we continue to test the platform for an optimal experience before it is made widely available.

With Rogers and Bell supporting system integrated Wi-Fi Calling for iPhone users, it’s only a matter of time for TELUS to similarly announce support as well.